This invention relates to a dispenser for viscous or viscous products, which has a closure, which closure automatically closes the dispenser exit. More particularly, this invention relates to a dispenser having a closure where the closure opens before the flow of viscous product and closes after the flow of viscous product. The closure acts as a door or knife to assist in cutting off the product flow to maintain cleanliness.
These are a variety of dispensers for viscous products (viscosity range 150,000-600,000 CPS), which include a closure for the exit. Such a closure is used for hygienic reasons to keep the viscous product isolated from the environment when the dispenser is not in use. Such a closure could be one that is opened and closed manually. The closure could be threaded onto dispenser exit or attached to the dispenser and opened via a hinge. However, in all of these embodiments a person would have to remember to put the closure in place after use. It is preferred that the closure be automatically activated to open and close the dispenser exit when the dispenser is actuated, and in addition assist in product cutoff.
Dispensers that have automatically opening and closing closures for a dispensing outlet are disclosed in U.S. Pat. No. 4,684,044; U.S. Pat. No. 4,691,847; U.S. Pat. No. 4,715,518 and U.S. Pat. No. 4,872,596. In several of these patents the closure over the dispensing outlet also functions as a valve that is necessary for the operation of the dispenser. In the present dispenser the pump valves are located within the pump body with the closure solely being for sanity purposes and to keep the product at the dispenser opening from drying out and forming a crust at the dispenser outlet, and stopping product flow in a clean manner by assisting product cutoff.
The present dispenser has an ergonomic shape and is of the type where the outlet of the dispenser is automatically covered by a closure when the dispenser is not in use and is being stored. An objective is to have the outlet of the dispenser covered for sanitary reasons, to prevent the product in the area of the outlet from drying out and forming a crust or dried plug at the outlet exit. Another is for the closure to assist in the cutoff of any part of the product as the main charge of viscous product is being sucked back into the dispenser upon the cessation of dispensing.
The ergonomic shape is to make the dispenser easy to grip and to hold in one hand, and to operate using one hand. This alone provides a clear difference compared to current package forms for dispensing viscous products.
The dispenser is comprised of a product chamber and a pump chamber. The product chamber will, in one embodiment, be unitary with the dispenser and in another embodiment be a refill container that can be inserted into the dispenser to replace a container from which all of the product has been dispensed. A refill container would be inserted into the dispenser through the bottom of the dispenser.
The dispenser is comprised of a body with a supporting base at a lower end. On the upper end there is a dispensing outlet and adjacent the dispensing outlet, an actuator. The dispenser outlet is closed by a pivoting outlet door closure. Upon depressing the pump actuator the outlet door closure is pivoted open prior to the initiation of product flow from the dispenser. It remains open during dispensing and closes after dosing of the product has been completed. However, it does not close until a portion of the product has been drawn back down into the dispenser, i.e, sucked back, by the internal valving system. This will assist the closure as it moves to close the dispensing outlet. The closure also will cutoff product any portions of the product that have not flowed back into the dispenser.
Upon actuation of the dispenser, by depressing the actuator, product in the pump chamber is expelled from the pump chamber past the pump chamber outlet valve, through the outlet channel and outlet channel extension to the outlet opening. As the actuator is being depressed, a closure covering the outlet opening immediately is opened. This closure is opened prior to the flow of product from the dispenser. After the opening of the closure, a portion of the product is dispensed from the dispenser. Upon release of the actuator, the flow of product ceases and some of the product is sucked back down into the dispenser from the region of the dispenser outlet prior to the closure closing. There is a delay in the closing of this closure to preclude contact of the closure with the viscous product being dispensed. This is accomplished by keeping the pump chamber outlet valve open during part of the return of the actuator to its rest position and the structure of the connection of the actuator to the closure. The release of the actuator returns it to the upright position and refills the dispensing chamber with the next dose or product.